So I've read all the whitepapers, and I know that you can store up to 5 million list items in a list as long as you use folders.

What I'm after, is, has anyone written some nice recursion that gets a list, looks at all the folders in the list, and assigns list items either to a <2000 folder, or creates a new folder if one does not exist, and then stores list items there?

Same thing with list item retrival. Does anyone have a nice clean and fast method for getting all list items from a list <2000 at a time?

I've looked on google and here and haven't found a nice definitive guide for storing and retrieving list items from large lists with code samples, it's all been about the theory from what I can see.